KABUL—Military authorities in southern Afghanistan have detained and disarmed a group of 30 police officers, including an acting district police chief, for suspected links with Taliban insurgents, officials confirmed on Sunday.

The police chief of the restive Helmand province, Abdul Rahaman Sarjang, told reporters in the provincial capital of Lashkar Gah that Afghan troops detained the police personnel with the help of American military advisers in the Sangin district.

Sarjang said the operation sparked a brief clash that killed one police officer. He added that Sangin’s acting police chief Mohammad Nabi and other detainees are currently under investigation.

Afghan media has quoted unnamed army officials as saying that U.S. advisers suspected Nabi and other detainees were providing weapons and ammunition to the Taliban and were eventually planning to defect to the insurgents.

The U.S. military has not yet commented.

The United States has recently deployed several hundred more troops to Helmand to help Afghan forces halt insurgent advances in the poppy-producing, largest province of Afghanistan, a traditional Taliban heartland.

Afghan troops in recent days have abandoned several outposts in hotly contested districts of Helmand, though senior army commanders have cited tactical and logistic reasons for the controversial move.